Method for producing metal nanowires and silver nanowires

Patent metadata

Field	Value
Publication number	US-10099291-B2
Application number	US-201414893329-A
Country	US
Kind code	B2
Filing date	May 26, 2014
Priority date	May 24, 2013
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

Provided are a metal nanowire production method capable of producing long and thin metal nanowires, and metal nanowires produced thereby. A metal nanowire production method comprising, a step for preparing a solution containing a metal salt, a polymer, at least one selected from a group consisting of halides, sulfides, carbonates, and sulfates, and an aliphatic alcohol, and a step for heating and reacting the solution at the temperature of 100° C. to 250° C. for 10 minutes or more while maintaining a practical shear stress applied to the solution at 10 mPa·m or less, wherein, during the heating and reacting step, ultraviolet-visible absorption spectrum change of the solution is measured, and a reaction time is controlled on the basis of the ultraviolet-visible absorption spectrum information.

First claim

The invention claimed is:

1. A metal nanowire production method comprising, a step for preparing a solution containing a metal salt, a polymer, at least one selected from a group consisting of halides, sulfides, carbonates, and sulfates, and an aliphatic alcohol, and a step for heating and reacting the solution at the temperature of 100° C. to 250° C. for 10 minutes or more while maintaining a simplified shear stress applied to the solution at 10 mPa·m or less, wherein, during the heating and reacting step, ultraviolet-visible absorption spectrum change of the solution is measured, and a reaction time is controlled on the basis of the ultraviolet-visible absorption spectrum information.

2. A metal nanowire production method according to claim 1 , wherein the metal is at least one selected from a group consisting of gold, silver, copper, platinum, palladium, ruthenium, cobalt, nickel, molybdenum, indium, iridium, and titanium.

3. A metal nanowire production method according to claim 1 , wherein the metal salt is at least one selected from a group consisting of a nitrate, an organic carboxylate, a metal alkoxide, and a metal phenoxide.

4. A metal nanowire production method according to claim 1 , wherein the polymer is at least one selected from a group consisting of polyvinylpyrrolidone, poly-N-vinyl acetamide, poly-N-vinyl formamide, polyvinyl caprolactam, and polyacrylamide.

5. A metal nanowire production method according to claim 1 , wherein the aliphatic alcohol has a boiling point of 100° C. or more at 1 atmospheric pressure, and a viscosity of 10 Pa·s or less at 25° C.

6. A metal nanowire production method according to claim 1 , wherein the halide is selected from a group consisting of NaCl, CoCl 2 , SnCl 4 , CuCl 2 , NiCl 2 , FeCl 3 , ZnCl 2 , NaBr, NaI, KBr, KI, and quaternary ammonium salts represented by R 4 NCl, R 4 NBr, R 4 NI (wherein, R is an alkyl group having 1 to 12 carbons), the sulfide is selected from a group consisting of Na 2 S and K 2 S, the carbonate is selected from a group consisting of Na 2 CO 3 and K 2 CO 3 , and the sulfate is selected from a group consisting of Na 2 SO 4 and K 2 SO 4 .

7. A metal nanowire production method according to claims 1 , wherein metal is silver, the aliphatic alcohol is at least one selected from a group consisting of ethylene glycol and propylene glycol, and the at least one selected from a group consisting of halides, sulfides, carbonates, and sulfates has a concentration of 1×10 −8 M to 1×10 −2 M.

8. A metal nanowire production method according to claim 7 , wherein, ultraviolet-visible absorption spectrum of the solution is measured during the heating step, and the reaction is stopped at a point where a ratio (A420 nm/A350 nm) representing an absorption intensity at 350 nm (A350) relative to an absorption intensity at 420 nm (A420) is 2 or less, and an absorption intensity at 380 nm (A380) is more than a half of the peak absorption intensity at 380 nm.

9. A silver nanowire production method comprising, a step for preparing a solution containing a silver salt, a polymer, at least one selected from a group consisting of halides, sulfides, carbonates, and sulfates, and an aliphatic alcohol, and a step for heating and reacting the solution at the temperature of 100° C. to 250° C. for 10 minutes or more while maintaining a simplified shear stress applied to the solution at 10 mPa·m or less, wherein, during the heating and reacting step, ultraviolet-visible absorption spectrum change of the solution is measured, and a reaction time is controlled on the basis of the ultraviolet-visible absorption spectrum information.

10. A silver nanowire production method according to claim 9 , wherein the silver salt is at least one selected from a group consisting of a nitrate, an organic carboxylate, a silver alkoxide, and a silver phenoxide.

11. A silver nanowire production method according to claim 9 , wherein the polymer is at least one selected from a group consisting of polyvinylpyrrolidone, poly-N-vinyl acetamide, poly-N-vinyl formamide, polyvinyl caprolactam, and polyacrylamide.

12. A silver nanowire production method according to claim 9 , wherein the aliphatic alcohol has a boiling point 100° C. or more at 1 atmospheric pressure, and a viscosity of 10 Pa·s or less at 25° C.

13. A silver nanowire production method according to claim 9 , wherein the halide is selected from a group consisting of NaCl, CoCl 2 , SnCl 4 , CuCl 2 , NiCl 2 , FeCl 3 , ZnCl 2 , NaBr, NaI, KBr, KI, and quaternary ammonium salts represented by R 4 NCl, R 4 NBr, R 4 NI (wherein, R is an alkyl group having 1 to 12 carbons), the sulfide is selected from a group consisting of Na 2 S and K 2 S, the carbonate is selected from a group consisting of Na 2 CO 3 and K 2 CO 3 , and the sulfate is selected from a group consisting of Na 2 SO 4 and K 2 SO 4 .

14. A silver nanowire production method according to claim 9 , wherein the aliphatic alcohol is at least one selected from a group consisting of ethylene glycol and propylene glycol, and the at least one selected from a group consisting of halides, sulfides, carbonates, and sulfates has a concentration of 1×10 −8 M to 1×10 −2 M.

15. A silver nanowire production method according to claim 14 , wherein, ultraviolet-visible absorption spectrum of the solution is measured during the heating step, and the reaction is stopped at a point where a ratio (A420 nm/A350 nm) representing an absorption intensity at 350 nm (A350) relative to an absorption intensity at 420 nm (A420) is 2 or less, and an absorption intensity at 380 nm (A380) is more than a half of the peak absorption intensity at 380 nm.

Assignees

• Showa Denko Kk
• Univ Osaka

Inventors

• Suganuma Katsuaki
• Jiu Jinting
• Nogi Masaya
• SUGAHARA Tohru
• Araki Teppei
• Uchida Hiroshi
• Ohata Hideki
• Hara Masanao
• OKAZAKI Eri

Classifications

• B22F9/24 Primary

  starting from liquid metal compounds, e.g. solutions · CPC title

• B22F2304/05

  Submicron size particles · CPC title

• B22F2301/255

  Silver or gold · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title